Plasma thrombospondin 1 as a predictor of postoperative liver dysfunction.

BACKGROUND: Liver regeneration following liver resection involves a complex interplay of growth factors and their antagonists. Thrombospondin 1 has recently been identified as a critical inhibitor of liver regeneration by the activation of transforming growth factor ß1 in mice, and preliminary data seem to confirm its relevance in humans. This study aimed to confirm these observations in an independent validation cohort. METHODS: Perioperative circulating levels of thrombospondin 1 were measured in patients undergoing liver resection between January 2012 and September 2013. Postoperative liver dysfunction was defined according to the International Study Group of Liver Surgery and classification of morbidity was based on the criteria by Dindo et al. RESULTS: In 85 patients (44 major and 41 minor liver resections), plasma levels of thrombospondin 1 increased 1 day after liver resection (mean 51·6 ng/ml before surgery and 68·3 ng/ml on postoperative day 1; P = 0·001). Circulating thrombospondin 1 concentration on the first postoperative day specifically predicted liver dysfunction (area under the receiver operating characteristic (ROC) curve 0·818, P = 0·003) and was confirmed as a significant predictor in multivariable analysis (Exp(B) 1·020, 95 per cent c.i. 1·005 to 1·035; P = 0·009). Patients with a high thrombospondin 1 concentration (over 80 ng/ml) on postoperative day 1 more frequently had postoperative liver dysfunction than those with a lower level (28 versus 2 per cent) and severe morbidity (44 versus 15 per cent), and their length of hospital stay was more than doubled (19·7 versus 9·9 days). CONCLUSION: Thrombospondin 1 may prove a helpful clinical marker to predict postoperative liver dysfunction as early as postoperative day 1.

Neoadjuvant bevacizumab persistently inactivates VEGF at the time of surgery despite preoperative cessation.

BACKGROUND: When anti-VEGF (vascular endothelial growth factor) antibody bevacizumab is applied in neoadjuvant treatment of colorectal cancer patients with liver metastasis, 5-6 weeks between last bevacizumab dose and liver resection are currently recommended to avoid complications in wound and liver regeneration. In this context, we aimed to determine whether VEGF is inactivated by bevacizumab at the time of surgery. METHODS: Fifty colorectal cancer patients with liver metastases received neoadjuvant chemotherapy ± bevacizumab supplementation. The last dose of bevacizumab was administered 6 weeks before surgery. Plasma, subcutaneous and intraabdominal wound fluid were analysed for VEGF content before and after liver resection (day 1-3). Immunoprecipitation was applied to determine the amount of bevacizumab-bound VEGF. RESULTS: Bevacizumab-treated individuals showed no increase in perioperative complications. During the entire monitoring period, plasma VEGF was inactivated by bevacizumab. In wound fluid, VEGF was also completely bound by bevacizumab and was remarkably low compared with the control chemotherapy group. CONCLUSION: These data document that following a cessation time of 6 weeks, bevacizumab is fully active and blocks circulating and local VEGF at the time of liver resection. However, despite effective VEGF inactivation no increase in perioperative morbidity is recorded suggesting that VEGF activity is not essential in the immediate postoperative recovery period.

KRAS status and outcome of liver resection after neoadjuvant chemotherapy including bevacizumab.

BACKGROUND: The prognostic value of KRAS mutation in patients with colorectal cancer liver metastases (CLM) receiving neoadjuvant chemotherapy including bevacizumab before liver resection is unclear. METHODS: The KRAS and BRAF status of resected CLM was assessed in prospectively studied patients. Mutations were correlated with recurrence-free and overall survival. Only patients with remaining vital tumour cells in the resected specimen and those without disease progression were analysed; those with progressive disease did not undergo resection. RESULTS: A total of 60 patients were enrolled. Fifteen (25 per cent) had a KRAS mutation, but none of the 60 patients had a BRAF mutation. The radiological response to neoadjuvant chemotherapy including bevacizumab, assessed according to the Response Evaluation Criteria In Solid Tumours, was partial in 52 patients (87 per cent) and the remaining eight had stable disease. The partial response rate was similar in patients with a KRAS mutation and those with the wild-type gene (12 of 15 versus 40 of 45 patients; P = 0·400). KRAS mutation had a negative prognostic effect on recurrence-free survival (hazard ratio (HR) 2·48, 95 per cent confidence interval 1·26 to 4·89; P = 0·009) and overall survival (HR 3·51, 1·30 to 9·45; P = 0·013). CONCLUSION: This study provided further evidence for the prognostic importance of KRAS status in terms of recurrence-free and overall survival. Neoadjuvant chemotherapy including bevacizumab elicited a response, irrespective of KRAS status, in this selected group of patients with CLM.

Lymph node ratio after curative surgery for intrahepatic cholangiocarcinoma.

BACKGROUND: Intrahepatic cholangiocarcinoma (ICC) is rare but its incidence is rising worldwide. The value of lymph node dissection for ICC is under discussion; the current staging systems do not differentiate between numbers of involved nodes. METHODS: Ninety-three patients who underwent laparotomy for ICC between 1997 and 2007 were identified retrospectively; 46 who underwent curative resection and systematic lymphadenectomy around the hepatoduodenal ligament were analysed further. Univariable and multivariable regression analysis was performed to identify prognostic factors. RESULTS: Tumour size and advanced tumour stage were associated with worse overall and recurrence-free survival in univariable analysis. An increased ratio of positive to total harvested lymph nodes (LNR) was also prognostic for adverse outcome in lymph node-positive patients: crude hazard ratio 8.93 (95 per cent confidence interval (c.i.) 1.52 to 32.50) for overall survival and 8.76 (1.96 to 39.22) for recurrence-free survival. Adjusted hazard ratios for LNR in multivariable regression analysis were 9.81 (1.52 to 43.44) and 10.63 (2.04 to 55.31) respectively. The total number of retrieved lymph nodes was not related to survival or recurrence. CONCLUSION: LNR appears to be a good prognostic factor for survival or recurrence after curative resection for ICC.

Selective resection of colorectal liver metastases.

AIMS: Safety of liver surgery for colorectal cancer liver metastases after neoadjuvant chemotherapy has to be re-evaluated. PATIENTS AND METHODS: Two hundred Patients were prospectively analyzed after surgery for colorectal cancer liver metastases between 2001 and 2004 at our institution. Special emphasis was given to perioperative morbidity and mortality under modern perioperative care. RESULTS: There was no in-hospital mortality and the perioperative morbidity was 10% (20/200). Four patients had to be reoperated due to bile leak or intraabdominal abscess. The remainder either had infectious complications or pleural effusion and/or ascites requiring tapping. Variables strongly associated with decreased survival were T, N, G and UICC (International Union against cancer) classification of the primary, hepatic lesions>5 cm and elevated tumour markers. Short disease free interval and neoadjuvant chemotherapy without response predicted impaired recurrence free survival (RFS). Multivariate analysis revealed lymph node status and differentiation of the primary, presence of extrahepatic tumour and gender as factors associated with decreased survival. Administration of neoadjuvant chemotherapy was not associated with higher postoperative morbidity or prolonged hospital stay. CONCLUSIONS: Modern dissection techniques and improved perioperative care contributed to a very low rate of surgery-related morbidity (10%) and a zero percent mortality which was also observed in patients pretreated with neoadjuvant chemotherapy prior to resection. Liver resection in experienced hands has become a safe part in the potentially curative attempt of treating patients with metastatic colorectal cancer.

Histological response, pattern of tumor destruction and clinical outcome after neoadjuvant chemotherapy including bevacizumab or cetuximab in patients undergoing liver resection for colorectal liver metastases.

AIM: We investigated whether the type of antibody [bevacizumab (bev) or cetuximab (cet)] added to neoadjuvant combination chemotherapy before curative liver resection was associated with histological response, the pattern of tumor destruction and clinical outcome in patients with colorectal liver metastases (CLM). METHODS: We investigated 138 patients with KRAS wild-type status (codon 12, 13 and 61) who received neoadjuvant chemotherapy including bev (n = 101) or cet (n = 37). The primary endpoint was histological response. Secondary endpoints were necrosis and fibrosis of metastases, radiological response, recurrence-free survival (RFS) and overall survival (OS). RESULTS: Histological response was not significantly different between the two groups (P = 0.19). A significantly higher fraction of patients in the bev group showed necrosis of the metastases of ≥ 50% (P < 0.001), while a higher fraction of patients in the cet group showed fibrosis of ≥ 40% (P = 0.030). Radiological response was not significantly different (P = 0.17). Median RFS was significantly shorter in the cet group in univariable analysis (HR 1.59 (95% CI 1.00, 2.51), P = 0.049), but this difference did not remain significant in multivariable analysis (P = 0.45). The 3-year OS rate was not significantly different (P = 0.73). CONCLUSIONS: The addition of bevacizumab to combination chemotherapy showed more necrosis but less fibrosis of metastases compared to cetuximab and a trend towards higher histological and radiological response and longer RFS. Further investigations of biological tumor characteristics are required to individualize treatment combinations.

Plasma disposition of capecitabine and its metabolites 5'DFCR and 5'DFUR in a standard and dose-intensified monotherapy regimen.

PURPOSE: In view of a potential gain in anticancer activity in advanced colorectal cancer (ACRC), there has been considerable interest in using a higher than the approved standard dose of capecitabine (CCB) combined with oxaliplatin. This pharmacokinetic study was designed to evaluate whether CCB is metabolized at the same extent when administered as a monotherapy in two different dose regimens, comparing standard dose (CCB 1) and intensified dose (CCB 2). PATIENTS AND METHODS: Seven patients suffering from ACRC received subsequently two CCB schedules: In the standard schedule, 1,250 mg/m² CCB p.o. twice daily for 2 weeks was administered, after a pause of 1 week, a dose-intensified CCB 2 schedule was given: 1,750 mg/m² CCB p.o. twice daily for 1 week to be followed by 1 week rest. Due to this paired cross over design a direct comparison for each single patient was feasible. RESULTS: In both schedules, mean peak plasma concentrations of CCB occurred at about 50 min, those of metabolites shortly later (range 54-80 min). Peak plasma concentrations were about 10% (CCB, DFCR) and 40% (DFUR) higher in the CCB 2 regimen. According to the higher dose of CCB in the dose-intensified regimen (+40%), the AUC(last) values increased by 34% (CCB), 20% (DFCR) and 58% (DFUR), respectively. CONCLUSION: The results indicate that higher doses of CCB are metabolized approximately dose-dependent compared to the standard dose. No indices for a saturation of metabolizing processes or any significant delay of elimination rate was observed. The immediate 5FU precursor DFUR was formed at a 50% higher extent (expressed as AUC(last) values) than in the standard CCB 1 schedule. From the pharmacokinetic point of view, this increased formation rate suggests clinical importance in regard to metabolic activation of CCB.

Thrombospondin-1: a unique marker to identify in vitro platelet activation when monitoring in vivo processes.

BACKGROUND: Measuring platelet activation in patients has become a potent method to investigate pathophysiological processes. However, the commonly applied markers are sensitive to detrimental influences by in vitro platelet activation during blood analysis. OBJECTIVES: Protein isoforms of platelet-derived thrombospondin-1 (TSP-1) were investigated for their potential to identify in vitro platelet activation when monitoring in vivo processes. METHODS: TSP-1 was determined in plasma, serum or supernatant of purified platelets by ELISA and immunoblotting and was compared with standard markers of platelet activation. A collective of 20 healthy individuals and 30 cancer patients was analyzed. RESULTS: While in vitro platelet degranulation led to a selective increase in the 200-kDa full-length molecule, an in vivo process involving platelet activation such as wound healing resulted in the predominant rise of the 140-kDa TSP-1 protein. The physiological ratio of circulating TSP-1 variants was determined and a cut-off level at 1.0 was defined to identify plasma samples with artificial in vitro platelet activation exceeding the cut-off level. In contrast, cancer patients known to frequently exhibit increased in vivo activation of platelets presented with a significantly decreased ratio of TSP-1 variants as compared with healthy volunteers. CONCLUSIONS: In comparison to standard platelet markers, TSP-1 constitutes a sensitive and stable parameter suited to monitor in vitro platelet activation. The analysis of TSP-1 protein isoforms further offers a valuable tool to reliably discriminate between in vitro and in vivo effects, to exclude variability introduced during blood processing and improve clinical monitoring.

Bevacizumab protects against sinusoidal obstruction syndrome and does not increase response rate in neoadjuvant XELOX/FOLFOX therapy of colorectal cancer liver metastases.

AIM: In patients suffering from colorectal cancer liver metastases, 5-fluorouracil-based chemotherapy plus oxaliplatin ensures superior response rates at the cost of hepatic injury. Knowledge about the consequences of bevacizumab on chemotherapy-induced hepatic injury and tumor response is limited. METHODS: Resected liver specimens from patients of two prospective, non-randomized trials (5-fluorouracil/oxaliplatin+/-bevacizumab) were analyzed retrospectively. Hepatotoxicity to the non-tumor bearing liver was evaluated for sinusoidal obstruction syndrome, hepatic steatosis and fibrosis. Tumor response under chemotherapy was assessed according to Response Evaluation Criteria in Solid Tumors (RECIST). RESULTS: Bevacizumab decreased the severity of the sinusoidal obstruction syndrome. Bevacizumab had no impact on hepatic steatosis and fibrosis. The addition of bevacizumab to chemotherapy had no effect on tumor response compared to combination chemotherapy alone. CONCLUSIONS: This analysis shows that bevacizumab protects against the sinusoidal obstruction syndrome and thus provides the histological explanation of the safe use of bevacizumab prior to liver resection. Furthermore, we show that bevacizumab does not improve tumor response according to RECIST.

Systemic bevacizumab (Avastin) therapy for exudative neovascular age-related macular degeneration. The BEAT-AMD-Study.

BACKGROUND: Double-blinded, randomised, prospective, pilot-study to determine the effect of systemic bevacizumab therapy. METHODS: Subjects with fibrovascular pigment epithelial detachment, subfoveal choroidal neovascularisation extending under the geometric centre of the foveal avascular zone and/or macular thickness of at least 300 microm in both eyes were included. Sixteen eyes were included and randomised equally to receive either three infusions of 5 mg/kg Avastin or 100 ml of 0.9% sodium chloride every 2 weeks. The main outcome measure was the lesion size. The follow-up time was 24 weeks. RESULTS: Throughout the 24-week follow-up, the lesion size and macular thickness decreased in the Avastin group by 0.5 (SD 0.08) mm and 103.6 (14.9) microl respectively. In both groups, visual acuity remained stable in seven eyes and decreased in one eye. At the end of follow-up, 50% of the eyes in the Avastin group became fibrotic, 37.5% remained unchanged, and 12.5% developed a subretinal bleeding. There was a treatable rise in blood pressure after Avastin treatment. CONCLUSION: Systemic Avastin could be offered to patients with exudative age-related macular degeneration in both eyes and/or patients who refuse intravitreal injections if blood pressure is normal and there is no history of thrombosis.

Patterns of hepatotoxicity after chemotherapy for colorectal cancer liver metastases.

AIM: The aim of this study was to assess chemotherapy associated hepatotoxicity after 3 months' treatment and to correlate patterns of hepatotoxicity with perioperative morbidity. METHODS: Liver specimens of 50 patients with liver metastases from colorectal cancer receiving XELOX or FOLFOX4 for six cycles and 13 specimens of non-chemotherapy patients subjected to liver resection were analyzed. Different patterns of hepatotoxicity were evaluated according to widely accepted pathohistological scores. Furthermore, the histomorphological findings were correlated with perioperative morbidity. RESULTS: Steatosis grades did not differ among the chemotherapy treated groups and non-chemotherapy patients. Chemotherapy showed an independent effect on fibrosis stage. Age and chemotherapy were independently associated with sinusoidal dilatation. Centrilobular vein fibrosis correlated with administration of chemotherapy. Higher fibrosis stages were associated with increased transfusion requirements. CONCLUSION: XELOX and FOLFOX4 do not correlate with the development of steatosis or steatohepatitis. We do not detect a difference in liver injury between the XELOX and FOLFOX4 group. Although 5-fluorouracil based chemotherapy may cause profound changes in liver parenchyma, it can be safely applied. However, age and oxaliplatin predispose for the development of sinusoidal dilatation; therefore caution must be taken in old patients treated with oxaliplatin.